IBM Administrative Terminal System
Encyclopedia
The IBM Administrative Terminal System, also known as ATS/360, was an IBM contributed program which provided, for the end-user customer of IBM System/360 systems, a system which was quite similar to the proprietary IBM Service Bureau Corporation product which ran on IBM 1440 systems or on IBM System/360 DOS systems.
ATS provided comprehensive text and data tools including entry, archiving and retrieving, formatting and printing. Utilizing ATS, a large business could maintain all its end-user documents, revising and printing new versions of these as required. Also using ATS, a large law practice could maintain its client files, including witness statements and depositions, and several landmark legal decisions were significantly assisted using ATS.
Initially, ATS/360 supported only IBM 2741
terminals. Later, support was added by user groups for 2741 terminals with the "break feature" and for IBM 1050 terminals. The Magnetic Card Selectric Typewriter (MC/ST), which could emulate a 2741, was also supported.
ATS/360 was designed exclusively for IBM 2311 and IBM 2314 direct access storage facilities (for "working storage" and for "permanent storage") and for IBM 2400/3400 tape drives (for "offline storage" and for offline "format and print" tapes).
An IBM hardware RPQ provided the IBM 1403
Model N1 printer's TN print train with characters which simulated the IBM Selectric typewriter Courier 72 type ball characters identically, thereby allowing machine printed documents to be manually corrected, or for manually inserted text, as required.
An IBM program RPQ added support for the IBM 3330 direct access storage facility, and this RPQ was applied by most users of ATS/360 which had migrated to IBM System/370 processors.
Support beyond SVS was not offered by IBM, but Peter Haas, formerly with Litton Systems Inc, and later with Amdahl Corp, added support for MVS in general, and for APs and MPs in particular, and a large number of ATS/360 systems thereby remained in use well into the MVS/370 era.
Technically, ATS/360 was very efficient in its use of main storage, and it was not uncommon to support quite a few terminals in a minimum size region.
ATS/360 was also very efficient in its use of system resources, and it had its own task dispatcher which worked seamlessly with PCP, MFT/MFT-II and MVT, for which it was originally designed, with SVS and, later, with Haas's support, with MVS.
ATS/360's input/output operations utilized EXCP
exclusively. Task switching was accomplished asynchronously as an extension of ATS/360's EXCP appendages and synchronously as an extension of ATS/360's Type 1 SVC, SVC 255. Thereby, ATS/360 could support quite a number of online (terminal) and offline (peripheral) tasks even on PCP (which otherwise supported just a single task).
ATS/360 provided its own access methods and file formats. Offline "format and print" tapes could be printed using standard OS utilities as these tapes were compatible with BSAM
.
ATS provided comprehensive text and data tools including entry, archiving and retrieving, formatting and printing. Utilizing ATS, a large business could maintain all its end-user documents, revising and printing new versions of these as required. Also using ATS, a large law practice could maintain its client files, including witness statements and depositions, and several landmark legal decisions were significantly assisted using ATS.
Initially, ATS/360 supported only IBM 2741
IBM 2741
The IBM 2741 was a printing computer terminal introduced in 1965.It combined a ruggedized Selectric typewriter mechanism with IBM SLT electronics and an RS-232-C serial interface. It operated at about 14.1 characters per second with a data rate of 134.5 bits/second...
terminals. Later, support was added by user groups for 2741 terminals with the "break feature" and for IBM 1050 terminals. The Magnetic Card Selectric Typewriter (MC/ST), which could emulate a 2741, was also supported.
ATS/360 was designed exclusively for IBM 2311 and IBM 2314 direct access storage facilities (for "working storage" and for "permanent storage") and for IBM 2400/3400 tape drives (for "offline storage" and for offline "format and print" tapes).
An IBM hardware RPQ provided the IBM 1403
IBM 1403
The IBM 1403 line printer was introduced as part of the IBM 1401 computer in 1959 and had an especially long life in the IBM product line. The original model could print 600 lines of text per minute and could skip blank lines at up to 75 inches/second. The standard model had 120 print...
Model N1 printer's TN print train with characters which simulated the IBM Selectric typewriter Courier 72 type ball characters identically, thereby allowing machine printed documents to be manually corrected, or for manually inserted text, as required.
An IBM program RPQ added support for the IBM 3330 direct access storage facility, and this RPQ was applied by most users of ATS/360 which had migrated to IBM System/370 processors.
Support beyond SVS was not offered by IBM, but Peter Haas, formerly with Litton Systems Inc, and later with Amdahl Corp, added support for MVS in general, and for APs and MPs in particular, and a large number of ATS/360 systems thereby remained in use well into the MVS/370 era.
Technically, ATS/360 was very efficient in its use of main storage, and it was not uncommon to support quite a few terminals in a minimum size region.
ATS/360 was also very efficient in its use of system resources, and it had its own task dispatcher which worked seamlessly with PCP, MFT/MFT-II and MVT, for which it was originally designed, with SVS and, later, with Haas's support, with MVS.
ATS/360's input/output operations utilized EXCP
Execute Channel Program
In IBM mainframe operating systems, Execute Channel Program is a supervisor call for low-level device access, where the programmer is responsible for providing a list of device-specific CCWs, that is, a Channel Program, to be executed by I/O channels, control units and devices...
exclusively. Task switching was accomplished asynchronously as an extension of ATS/360's EXCP appendages and synchronously as an extension of ATS/360's Type 1 SVC, SVC 255. Thereby, ATS/360 could support quite a number of online (terminal) and offline (peripheral) tasks even on PCP (which otherwise supported just a single task).
ATS/360 provided its own access methods and file formats. Offline "format and print" tapes could be printed using standard OS utilities as these tapes were compatible with BSAM
Basic sequential access method
In IBM mainframe operating systems, Basic sequential access method is an access method to read and write datasets sequentially. BSAM is available on OS/360, OS/VS2, MVS, z/OS, and related high-end operating systems....
.